where \(\theta _0\)  represents the azimuth angle of the targetIn radar related literature, the direction of the target is typically known to the transmitter since it can be readily estimated [1]}-[2]} at previous observations, or given by the center of angular sector-of-interest., \(\Delta \)  denotes the antenna spacing and \(\lambda \)  the wavelength.
The matrix \(\mathbf {Q} \in \mathbb {C}^{N \times M}\)  denotes the interfering channel between the BS and the radar receiver, and \(\mathbf {n}_\mathrm {r}\in \mathbb {C}^{M}\)  is the AWGN with \(\mathbf {n}_\mathrm {r} \sim \mathcal {CN}(0, \sigma _{\mathrm {r}}^2\mathbf {I})\) .
By defining \(\mathbf {A}\triangleq \mathbf {a}_\mathrm {r}(\theta _0)\mathbf {a}_\mathrm {t}^H(\theta _0)\) , the received signal at the radar can be concisely re-written as
\(\mathbf {y}_\mathrm {r}=\alpha \mathbf {A}\mathbf {F}\mathbf {c}+\mathbf {Q}^H\mathbf {W}\mathbf {s}+\mathbf {n}_\mathrm {r}.\) 
